Is Buffy 'Summers' an INTP?
I really think she's an INTP, now that I think about it.
Because, even though she's got her gang, she sometimes needs to go it alone for whatever reason. She's smart, witty, funny and thinks outside the box. Plus she's very straight forward and even though she'd listen to whatever Giles is saying about a demon, she'd probably be thinking about it/building a mental picture of it/running a simuation in her head; or whatever, and given all that Giles is saying, be able to come up with
'Big, Icky Slimey Monster-Demon'
which, would be more or less be correct.